1. Field
Embodiments relate to a washing machine, and more particularly, to a washing machine including a washing tub that is capable of improving washing effect.
2. Description of the Related Art
In general, a washing machine is classified as a pulsator type washing machine and a drum type washing machine according to a washing method. Both the pulsator type washing machine and the drum type washing machine include a tub and a washing tub.
In the pulsator type washing machine, a rotation shaft of the washing tub in which washing is to be performed, is provided perpendicular to the ground. A pulsator for generating a washing water current is installed at a lower portion of the washing tub. In the pulsator type washing machine, the pulsator is rotated by a motor in a state in which laundry and detergent water are put into the washing tub, and the laundry put into the washing tub is agitated together with washing water so that dirt stained on the laundry can be removed.
In the drum type washing machine, washing is performed by a fall. A lifter is disposed in the washing tub so as to lift the laundry in an upward direction.
In the pulsator type washing machine and the drum type washing machine, through holes through which water in the tub can be introduced into the washing tub and water in the washing tub can be discharged from the washing tub when drainage and dehydration operations are performed, are provided in a circumference of the washing tub.
In the related art, through holes are arranged in an inner surface of a flat washing tub. In this case, friction between the inner surface of the washing tub and the laundry is not large, which causes a limitation in improving washing effect caused by friction.
Also, in order to solve the problem, protrusions that protrude in an inward direction of the washing tub are formed. However, a height of each of the protrusions is low, and a contact area between the protrusions and the laundry is small, which is less effective.